Four-time Olympic champion Laura Kenny has pulled out of the Track Cycling World Championships because of illness.

The 26-year-old Briton, who was due to race in Friday’s omnium, said she “let the girls down” after missing out on gold to Australia in the women’s team pursuit on Thursday.

Olympic champion Katie Archibald will replace her in the omnium in Poland.

“I haven’t been feeling right all week for reasons we’re not sure of,” said Kenny.

“But we do know my performances in the team pursuit over the last two days have been well off where I have been in training over the last two weeks.

“I would have given the omnium my best shot and I really wanted to do it, but, with the depth of the squad, it was decided that it was better that I didn’t compete and give someone else the opportunity.”

British Cycling performance director Stephen Park said: “It is the right decision for both herself and her team-mates.”